FIG. 3 is a top. front, perspective view and FIG. 4 is a. bottom, rear perspective view of a modification of the building block showing my new design.

The dominant feature of applicants building block design resides in a plurality of evenly spaced, vertically and deeply striated panels of uniform width on at least the outer face of the building block, and additionally on end faces of corner blocks.

1 claim:

The ornamental design for a building block. substantially as shown and described.